1. Technical Field
This invention relates generally to card readers which accept and interact with microprocessor-equipped cards (e.g., so-called "smart cards"). In particular, the invention provides a card reader which accepts different types of smart cards and emulates various peripheral devices such as magnetic stripe readers, bar code readers, and Wiegand effect readers.
2. Related Information
The need to store information in a portable and compact form has led to the development of various types of storage media and peripheral devices which interact with the storage media. For example, cards containing magnetic stripes have been developed to store a customer's bank account information, so that the customer can insert the magnetic card into an ATM machine and have certain information quickly and automatically exchanged with a bank. Similarly, Wiegand-effect cards containing a plurality of special wires have been used to store pre-coded information onto a portable card which can then be inserted into a suitable reader, which upon activation by the card unlocks a door or activates a parking garage gate. Well-known bar code technology allows a library patron's account information to be quickly entered and correlated with bar-coded books to be checked out from the library. These various media and reader devices have proliferated into numerous applications such as cafeteria meal plans, access control, and point-of-sale credit and debit transactions. Unfortunately, the media are incompatible with each other, resulting in the need for each customer to maintain several different cards for a bank, library, parking garage, and the like.
More recently, microprocessor-equipped cards ("smart cards") have been developed to allow larger quantities of information to be stored onto a single medium. Various manufacturers now provide different types of smart cards with different memory sizes, microprocessor types, and operating systems. The development of these cards can provide the basis for eliminating different types of information media altogether and consolidating different types of information on a single card.
Unfortunately, existing systems which support magnetic cards, bar-code stripes, and Wiegand effect cards cannot be easily retrofitted to use the newer smart cards. For example, replacing a cafeteria plan system which reads magnetic cards would require the replacement of the card reading terminals and the installation of a new type of terminal which could interact with the smart cards. Additionally, expensive and time-consuming software changes would be required in the central computer to interact with the smart cards. Thus, there exists a problem in transitioning existing systems to newer smart card technology.
Even if existing systems can be transitioned to smart card technology, there remains a problem of incompatibility among different types of smart cards. For example, different smart card vendors, while providing cards which generally comply with an ISO standard for electrical contacts and the like, unfortunately have failed to ensure that all cards provide a standard set of functions or software interfaces which can be used across different vendors'cards. In other words, designing a card reader to work with one vendor's smart cards will not ensure that another vendor's smart cards can be used in the reader. Other inventors have proposed features which would allow certain hardware-specific differences to be accommodated (see, e.g., U.S. Pat. No. 5,070,233, which proposes a circuit allowing different clock frequencies among smart cards to be used). However, more serious incompatibilities remain in that different operating systems, functions, and software interfacing techniques are used across different vendors' smart cards. For example, one vendor's cards may provide certain file security features, while another vendor's cards do not, or provide them in a different (and incompatible) manner. One vendor's cards may provide on-card stored-value purse debit and credit functions, while another vendor's cards do not. One vendor's cards may provide file-level access features, while another vendor's cards do not. These incompatibilities present a barrier to using the newer smart card technology, because integrators may become dependent on a particular vendor for smart cards, preventing price reductions due to lack of competition. Accordingly, there exists a problem in that remaining incompatibilities across smart card vendors inhibit the use of a standard interfacing technique for smart cards.
Finally, conventional smart card readers cannot be readily modified to add new features. Adding new features or compatibility modes typically requires changes to the card reader hardware or requires that the unit be removed for servicing. Thus, modifications become expensive and inconvenient.